Sand-blast apparatus.



UNITED STATES PATENT OFFICE.

Patented December 22, 1903;

NEAL F ARNHAM, OF CHICAGO, ILLINOIS.

SAND-BLAST APPARATUS.

SPECIFICATION formingpart of Letters Patent No. 747,396, dated December22, 1903. Application filed April 10, 1903. serial No. 151,998. (Nomodel.)

To aZZ whom/it may concern; e

Be it known that I, NEAL FARNHAM, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented certain new and useful Improvements in Sand-Blast Apparatus;and I y do declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same, reference being hadto the accompanying drawing, and to the figures of reference markedthereon, which forms a part of this specification. 1

invention ratus; and it has for its object to produce such an apparatusin which the sand will pass from the reservoir or tank by gravity aloneor by gravity aided by compressed air within the e the point of itsapplication.

It has, further, for its purpose to provide a coupling between thevertical discharge-pipe leading from the sand-tank, the sand-carryinghose, and the air-blast-supply pipe, arranged so that the coupling willstand at an oblique angle to the longitudinal axis of thedischarge-pipe, whereby the air-blast will be projected at an obliqueangle across the discharge-mouth of the vertical discharge-pipe, thepurpose of the first and second stated objects being to facifitate thefreer passage of the sand from the tank through the discharge and intothe sand-carrying hose and without clogging of the sand at either end ofthe discharge pipe, which otherwise would be liable to occur by reasonofback pressure of air in the discharge-pipe and condensation ofmoisture in the air-blast.

To the accomplishmentof the foregoing and such other objects as mayhereinafter aprelates to a sand-blast appabeing bad to the accompanyingdrawing, forming a part hereof, and in which the figure is a sideelevation of a sand-tank having my inven tion applied, a portion of theupper part of the tank being broken away.

In the drawing the numeral 1 designates a tank of any suitableconfiguration and dimensions designed to hold the sand. From the bottomof the tank leads a discharge-pipe 2, provided with suitable valves orvalve 3 to regulate the flow of sand through the pipe. To the lower endof the discharge-pipe is attached a Y-coupling 4, which is inclined tothe pipe2 and, as shown, stands obliquely or at an angle of aboutforty-five degrees, more or less, to the longitudinal axis of thedischarge-pipe. To one end of this coupling is attached, by a nipple 5or otherwise, a sand carrying hose 6 of any desired length to lead tothe point of application of the sand-blast, which hose may be of pliablematerial or of rigid material provided with any desired number offlexible joints 6. To the other end of the coupling is connected anair-blast pipe '7, to which compressed air is supplied through a T orother coupling 8 from a suitable. source of supply. The other end of thepipe 7opensinto the upper part of the tank 1, and said pipe is providedwith a valve 9,by which the supply of air to the tank may be regulatedor entirely out off, and it is also provided with a valve 10, by whichthe supply of compressed air to the blast-nozzle may be controlled. Atthe point where the air-blast pipe 7 connects with the inclined coupling4 it is provided with a nozzle or jet 11, which enters the coupling, sothat its point of discharge will lie below the discharge-mouth of thedischarge-pipe 2, leading from the tank, the best results being obtainedwhen itspoint of discharge is about midway of the discharge-mouth of thedischarge-pipe. By thus positioning the airblast nozzle the air isprojected across the mouth of the discharge-pipe 2 without the blastpassing up into the discharge-pipe and at the same time creates asuction across the discharge-pipe and down through the same, so that thedownflow of the sand through the pipe is greatly facilitated. At thesame time the force of the airblast from the nozzle across the mouth ofthe discharge-pipe strikes the sand as it issues from the mouth of thepipe and propels it with velocity away from the pipe and through thecarrying-hose and prevents any backflow or back pressure from the hoseor coupling and into the dischargepipe. If this back pressure werepermitted, it would not only retard the downflow of the sand, but itwould also result in the sand becoming moist from condensation of thecompressed air, and thus the pipe would become clogged and the eflicientworking of the device interfered with. The inclination of'the couplingat the lower end of the dischargepipe also aids in the rapid flow of thesand from the mouth of the discharge-pipe, so as to aid in preventingbackflow or back pressure of air.

By adjustment of the valve 9 more or less pressure of air may beadmitted to the tank to assist the outflow of sand therefrom and itsoutflow regulated to a nicety, or the air may be entirely out 01f fromthe tank.

The tank may be supported from the ground upon any suitable stand orotherwise supported.

I have indicated on the drawing the preferred dimensions of the parts;but they may be varied within reasonable limits.

Having described my invention and set forth its merits, What I claimis- 1. A sand-blast apparatus comprising the tank, the discharge-pipeleading from it, the

compressedair-supply pipe, sand-carrying inclined coupling at the lowerend of the discharge-pipe, the compressed-air-su pply pipe, thesand-carrying hose, and the air-blast nozzle entering the inclinedcoupling and having its point of discharge beneath the month of thedischarge-pipe leading from the tank, substantially as described.

3. A sand-blast apparatus comprising the tank, the discharge-pipeleading from it, to the sand-carrying hose, the compressed-airsupplypipe opening into the upper part of the tank and having the upper andlower controllingvalves, the inclined coupling between the sand carryinghose, the compressed-air-supply pipe and the dischargepipe from thetank, and the air-blast nozzle having its point of discharge in theinclined coupling beneath the mouth of the dischargepipe from the tank,substantially as described.

In testimony whereof I aflix my signature in presence of two witnesses.

NEAL FARNHAM. Witnesses:

W. G. HENDERSON, GEO. W. REA.

